Three men arrested in a series of raids Wednesday in east London are suspected of having been in the final stages of plotting a terror attack in the British capital similar to the murderous rampage carried out last Saturday at London Bridge, say officials.

The men, all in their 30s, are not connected to last week's van-and-knife attack in the London Bridge and Borough districts of the capital that left eight dead and 48 injured, say police officers.

Video of recent attack

The news of the arrests came as new video footage emerged of the dramatic shooting of the London Bridge attackers by armed police last Saturday. It shows officers leaping out of a moving police car to shoot the men in a few seconds of frenetic activity, bringing an end to a killing spree that lasted eight minutes.

The footage, taken by a local resident, has been circulated on social media sites.

Other footage has also emerged of the three London Bridge attackers, who have been identified as Khuram Shazad Butt, Rachid Redouane and Youssef Zaghba, meeting outside an all-Muslim gym the trio frequented in east London five days before the attack.

In the video obtained by The Times newspaper, the three are seen hugging and laughing outside the Ummah Fitness Center near where Butt lived with his wife and two young children.

The men appear to want to evade surveillance.

Redouane is seen placing his cellphone on a builder's sack nearby before the men walk away. Presumably, they feared the phone was bugged. They are out of view of the CCTV camera for 10 minutes and when they return Redouane retrieves his phone.

The footage of the meeting outside the gym will reinforce pressure on the British intelligence services to explain why the three were not under full-time surveillance.

The Ummah Fitness Center was once run by a man accused of helping to train the Islamic extremists responsible for the coordinated July 7, 2005, underground train bombings in London, Britain's first-ever Islamist suicide attack.

Fifty-two people were killed across the city in the 2005 coordinated strike that left more than 700 injured.

Muslims attend an event near the scene of the recent attack at London Bridge and Borough Market in central London, Britain June 7, 2017.

Missed chances

The British intelligence service, MI5, has been accused of missing a string of chances to identify Butt as a high-risk militant.

On Tuesday The New York Times reported that in 2015 FBI informant Jesse Morton, a one-time al-Qaida recruiter, warned his American handlers about the London Bridge terrorist. "Khuram Butt was on our radar rather a lot," he told the newspaper.

Questions are also being asked about why the British security services didn't act on information supplied by Italian police on Zaghba, an Italian-Moroccan, who had been stopped at Bologna airport last year on suspicion he was heading to join the Islamic State in Syria.

Italian authorities say they informed British intelligence agencies about him and uploaded his details to a European Union database that's designed to trigger an alert to passport control officers.

Officer injured in attack

Meanwhile, the rookie transport policeman who was stabbed in an eye while tackling the London Bridge terrorists armed only with a baton issued a statement Wednesday saying he "did everything I could" to stop them.

He has not been named by the authorities. He was one of the first officers to confront the London Bridge assailants.

"I am truly moved and overwhelmed by all the support and comments that I've received, not only from people in this country, but across the world," the officer said.

He has been hailed as a national hero, but he dismissed the description.

"Like every police officer who responded, I was simply doing my job," he said. "I didn't expect the level of love and well wishes I have received. I feel like I did what any other person would have done. I want to say sorry to the families that lost their loved ones."